Abstract

We demonstrate 30 times enhanced flux of relativistic electrons by a siliconnanowire coated target excited by 30 fs, 800 nm laser pulses at an intensity of 3 × 1018 W cm−2. A measurement of the megaampere electron current via induced megagauss magnetic field supports the enhancement feature observed in the electron energy spectrum. The relativistic electrons generated at the front of nanowire coated surface are shown to travel efficiently over 500 μm in the insulating substrate. The enhanced hot electron temperature is explained using a simple model and is supported by recent simulations.